[PATCH] refactored

[Wei Yang]

Signed-off-by: Lorenzo Stoakes <ljs@xxxxxxxxxx>
---
 mm/page_vma_mapped.c | 20 +++++++++++++++-----
 1 file changed, 15 insertions(+), 5 deletions(-)

diff --git a/mm/page_vma_mapped.c b/mm/page_vma_mapped.c
index 2ccbabfb2cc1..17dff8aab9f9 100644
--- a/mm/page_vma_mapped.c
+++ b/mm/page_vma_mapped.c
@@ -269,14 +269,24 @@ bool page_vma_mapped_walk(struct page_vma_mapped_walk *pvmw)
 			/* THP pmd was split under us: handle on pte level */
 			spin_unlock(pvmw->ptl);
 			pvmw->ptl = NULL;
-		} else if (!pmd_present(pmde)) {
-			const softleaf_t entry = softleaf_from_pmd(pmde);
+		} else if (pmd_is_device_private_entry(pmde)) {
+			softleaf_t entry;
+
+			pvmw->ptl = pmd_lock(mm, pvmw->pmd);
+			pmde = *pvmw->pmd;
+			entry = softleaf_from_pmd(pmde);

-			if (softleaf_is_device_private(entry)) {
-				pvmw->ptl = pmd_lock(mm, pvmw->pmd);
+			if (likely(softleaf_is_device_private(entry))) {
+				if (pvmw->flags & PVMW_MIGRATION)
+					return not_found(pvmw);
+				if (!check_pmd(softleaf_to_pfn(entry), pvmw))
+					return not_found(pvmw);
 				return true;
 			}
-
+			/* device-private pmd was split under us: handle on pte level */
+			spin_unlock(pvmw->ptl);
+			pvmw->ptl = NULL;
+		} else if (!pmd_present(pmde)) {
 			if ((pvmw->flags & PVMW_SYNC) &&
 			    thp_vma_suitable_order(vma, pvmw->address,
 						   PMD_ORDER) &&
--
2.54.0